Thatcham Tertiaries Operational Catchment
About
The Thatcham Tertiaries Groundwater Body (GWB) describes part of the Lambeth Group Strata (also known in the past as the Reading Beds) that lie around the edge of the Lower River Kennet valley. The Thatcham Tertiaries GWB is located around the axis of the western end of the London Basin syncline. The Thatcham Tertiaries GWB coincides with the eastern end of the River Kennet catchment, the southern end of the River Lambourn catchment and the southern side of the River Pang catchment. The Thatcham Tertiaries are a Secondary A Aquifer with water-bearing permeable strata that provide a low level of storage. Generally they consist of inter-bedded sands and clays that can also be laterally variable. Generally the lower units of the Lambeth Group are more sandy and can bear water. Since these sandy units sit directly over the Chalk aquifer, there can be hydraulic continuity between the Chalk and the base of the Lambeth Group. Given the close proximity of the Chalk any boreholes constructed in this area will usually be extended down into the Principal aquifer, therefore the Lambeth Group in this part of the country is little used for water abstraction (this contrasts with the London area where the Lambeth Group can provide significant volumes of water from the Thanet Sands). The main role for the water from the Thatcham Tertiaries in this area will be to contribute base flow to some of the local streams. In some locations particularly the Pang Valley, water will flow off the clay rich fields and make its way down into the sandy rich horizons of the Lambeth Group and into the Chalk via dolines or swallow holes. This can mean that pollutant transport has the potential to be rapid via these preferential pathways.
![No image available](/catchment-planning/photos/operationalcatchment/1233.jpg)
Classifications data for Thatcham Tertiaries Operational Catchment
Number of water bodies
The number of water bodies in the river basin district. It shows whether these are natural, artificial (such as canals and reservoirs) or have been modified ('heavily modified') for particular uses.
Water body categories | Natural | Artificial | Heavily modified | Total |
---|---|---|---|---|
River, canals and surface water transfers | 0 | 0 | 0 | 0 |
Lake | 0 | 0 | 0 | 0 |
Coastal | 0 | 0 | 0 | 0 |
Estuarine | 0 | 0 | 0 | 0 |
Groundwater | 1 | 0 | 0 | 1 |
Total | 1 | 0 | 0 | 1 |
Ecological status for surface waters
Table summarises the current ecological status of surface water bodies. Water bodies are classified as being at high, good, moderate, poor or bad ecological status or potential.
Ecological status or potential | Bad | Poor | Moderate | Good | High | Total |
---|---|---|---|---|---|---|
Number of water bodies | 0 | 0 | 0 | 0 | 0 | 0 |
Number of water body elements | 0 | 0 | 0 | 0 | 0 | 0 |
Chemical status for surface waters
Table summarises the current chemical status of water bodies. These are classified as being at good or fail.
Chemical status | Fail | Good | Total |
---|---|---|---|
Number of water bodies | 0 | 0 | 0 |
Number of water body elements | 0 | 0 | 0 |
Quantitative status for groundwater
Table summarises the quantitative status of groundwater water bodies. These are classified as being at good or poor.
Quantitative status | Poor | Good | Total |
---|---|---|---|
Number of water bodies | 0 | 1 | 1 |
Number of water body elements | 0 | 4 | 4 |
Chemical status for groundwater
Table summarises the chemical status of groundwater water bodies. These are classified as being at good or poor.
Chemical status | Poor | Good | Total |
---|---|---|---|
Number of water bodies | 0 | 1 | 1 |
Number of water body elements | 0 | 5 | 5 |
Challenges data for Thatcham Tertiaries Operational Catchment
Reasons for not achieving good status by business sector
The issues preventing waters reaching good status and the sectors identified as contributing to them. The numbers in the table are individual counts of the reasons for not achieving good status with a confidence status of 'confirmed' and 'probable', where the latest classification is less than good status. There may be more than one reason in a single water body. Note, table does not include reasons for deterioration.
Significant water management issue | Changes to the natural flow and level of water | Invasive non-native species | Physical modifications | Pollution from abandoned mines | Pollution from rural areas | Pollution from towns, cities and transport | Pollution from waste water |
---|---|---|---|---|---|---|---|
Agriculture and rural land management | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Domestic general public | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Industry | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Local & central government | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Mining and quarrying | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Navigation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
No sector responsible | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Other | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Recreation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Sector under investigation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Urban and transport | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Waste treatment and disposal | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Water Industry | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Total | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Objectives data for Thatcham Tertiaries Operational Catchment
Ecological status or potential objectives for surface water bodies
Table summarises the ecological status and ecological potential objectives set for water bodies in the river basin management plan. Each water body is only counted once in this table. Each water body objective consists of a target status and a date when it was, or is expected to be, met.
Status | Bad | Poor | Moderate | Good | High | Total |
---|---|---|---|---|---|---|
Total | 0 | 0 | 0 | 0 | 0 | 0 |
Chemical status objectives for surface water bodies
Including those with less stringent objectives and extended deadlines
Status | Fail | Good | Total |
---|---|---|---|
Total | 0 | 0 | 0 |
Quantitative status objectives for groundwater
Including those with less stringent objectives and extended deadlines
Status | Poor | Good | Total |
---|---|---|---|
By 2015 | 0 | 1 | 1 |
Total | 0 | 1 | 1 |
Chemical status objectives for groundwater
Including those with less stringent objectives and extended deadlines
Status | Poor | Good | Total |
---|---|---|---|
By 2015 | 0 | 1 | 1 |
Total | 0 | 1 | 1 |